Automatic shutoff mechanism for milking machines



. M. AUTOMATIC April 12, K EADES SHUT-OFF MECHANISM 1 FOR MILKING MACHINES Filed Nov. l2, 1947 r a r r r ////z INVENTOR M. K. EADES ATTORNEY.

Patented Apr. 12, 1 949 UNITED STATES PATENT OFFICE AUTOMATIC SHUTOFF MECHANISM FOR MILKING MACHINES 8 Claims. 1

This invention relates to milking machine mechanisms that will automatically stop the milking action when the milk flow ceases.

Such devices are not broadly new, because it has been recognized for many years that injury to cows can result from continuing the milking action after the milk supply is exhausted. I-Iowever, to the best of my knowledge, the prior known mechanisms have been impracticable for one reason or another and are not being generally used today.

A broad object of the present invention is to lprovide a milking machine shut-off mechanism that is practicable.

A more specic object is to provide a milking machine shut-olT-mechanism that is simple, inexpensive, easily cleaned and sterilized, and is particularly 4easy to manipulate.

The manner in which the foregoing objects, together with more specific objects and features of the invention, are realized will be understood :from the following description with reference to the drawing, in which:

Fig. 1 is a plan view of a milking machine tank cover incorporating the invention;

Fig. 2 is a vertical section through the tankA In accordance with conventional practice, a

milking machine includes a tank I having a cover II through which connections are made to hoses I2 leading to the teat cups and a hose I3 which leads to a pulsator or pump which provides the necessary suction to operate the teat cups. The milk withdrawn from the teat cups ows through the hoses I 2 into the tank I Il.

The cover II is secured to the tank I0 inv any known manner, and air tight connection is usually effected by the use of a gasket I5 of rubber or like material. Also in accordance with existing practice, a nipple I6 is provided as a part of the cover II for making connection with the hose I3 that leads to the pulsator. A safety valve II is commonly provided in the nipple I6 to prevent a sudden rush of air through the hose I3 into the tank I0 in the event the pulsator end of the hose is disconnected from the pulsator while there isl a vacuum in the tank I Il. It is also conventional practicev to provide ahandle I9 on the cover, II

2 Which handle actuates a valve 20 to break the vacuum in the tank and permit removal of the cover, by a rocking motion of the handle I9 counterclockwise (with reference to Fig. 2).

In accordance with the present invention, four valve casings are provided in the cover I I, one for each of the four hoses I2 extending to the teaty cups. These four valve casings are indicated at I8 in Fig. 1. They are all of identical construction and will be described with reference to Figs. 3 and 4.

Each valve casing I8 is constituted by a side wall I9 which rises upwardly from the main wall III of the cover II, and by a wall 2| which extends Ibelow the wall I I I and is closed by a bottom wall 22. The wall I9 is oval in horizontal section, as clearly appears -from Fig. l, whereas the lower wall 2| is cylindrical in shape. This cylindrical wall 2l denes the lower portion of a float chamber containing a float 23, which is preferably a hollow rubber ball adapted, when there is no liquid in the oat chamber, to rest against and seal a circular edge 24 in the bottom wall 22. To this end, the center portion of the bottom wall 22 is shaped in the segment of a sphere of smaller ydiameter than the oat 23. When the iloat 23 rests on the edge 24, it seals a bleeder hole 25 in the bottom wall 22.

The interior of the valve casing I8 is adapted to be communicated with the interior of the tank I (I, not only through the bleeder hole 25, but through an outlet passage 26 the upper end of which is adapted to be closed by a valve 21. Thus the valve 21 may be of soft rubber and secured to a valve arm 28 which is pivoted at its left end on a crossbar 29 secured to the upper end of a post 30 which rises from the coverplate III. As best shown in Fig. 4, the left end portion of the valve arm 28 is of channel cross section having downwardly depending flanges 28a in which pivot holes 28h are provided to receive the crossbar 29. Crossbar 29 may be formed o-f sheet metal riveted 'to the upper end of the post 30, and the outer ends of the crossbar may be of reduced width to extend into the holes 28h, the shoulders adjacent the reduced ends preventing lateral movement of the valve arm 28.

As shown in Fig. 3, the right end of the valve arm 28 extends across the oat chamber in which.

the float 23 is positioned, and when the oat is raised by the presence of milk in the oat chamber the valve is held open (the position shown in Fig. 3.)

While the milking operation is proceeding, the oat chamber contains milk which maintains the float 23 in upper position to hold the valve 21 open. However, it is necessary at the beginning of the milking operation to hold the valve 21 open by some other means until the float chamber has lled with milk. This means consists of a U- shaped wire latch member 32, the upper ends of which are extended outwardly into holes 33 in the anges 28a of the valve arm 28. Ordinarily, the latch member 32 hangs straightv downwardly as shown in Fig. 3. However, by swinging t-hey lower end of the member 32 over onto a stop shoulder 34 formed in the post 30 the latch member can be caused to retain thel valve 31 inropen position even though there is no milk in theffloat chamber. fills with milk, and the oat 23 risesagainst the valve arm 28, the lower end cfthe latch. member 32 is carried clear of the shoulder 34, whereupon the member 32 swings into the vertical position, and, when the float chamber empties of milk at the end of the milking operation, theval'vearm-28J is permitted to bring the valve 21 down against the valve seat at thev upper end` of the outlet passage 26, closing it 01T.

' Each of the teat hoses l2 may be connected to thevalve casing by a nippIeES'eXtendng from the side wall' i9. The upper end of each -valve casing may be closed by a glass cover 31, which has secured to its edge a gasket 38 Voi rubber or the like, which in turn rests on an intern-al ange 33 of the side wall I9. A tiny pinhole vent di) may be provided in the cover 31 torelieve the vvacuum within the valve casing after the valve 21 has closed, and the float 23 has sealed oi the bleederv hole 25. Breaking of the vacuum is necessaryinorder to eliminate the vacuum at the teat cups and permit the latter to fail clear of the teats.

The width of the valvecasing- `8- between the flange'` on oppositey sides of the valve casing is slightly less' than the diameter of the rubber float 23, so that while the oat can be forciblyinserted or removed it cannot accidentally fall out.

During theA milking operation, the covers 31 are firmly retained in place by the vacuum withinthe valve casing. During handling operations-the covers are held in place by friction of thegaskets 38 against the walls i9.

The device is operated as follows: At the beginning of the milking opera-tion, prior to attachment of the cover Il to the-tank-HL the cover is rocked counter-clockwise fromthe position shown in Fig. 3 through anangle somewhat in excess of 90. This causes' the valve arms 2t in all four of the valve casings IIS tofali by gravity against the cover plates 3T. At the same time, the latch members 32 fall by gravity over against their associated posts-3.` The cover plate is then rocked backinto normallposition as shown in Fig. 3, and duringthisv movement4 the' latch members 32 all comeV to rest against the shoulders 34, to hold" the valves 2/1 open. The dotted line showing in Fig. 3 shows the position of the valve during the return clockwise rockingv motion from the valve-seating position.

The cover is then secured tothe tanklll, and connection is made to the pulsator through the hose i3. The pulsator produces the usual' vacuum within the tank, which is transmittedv throughl the outlet passages 2S' to the valve-casings'l i8" and thence through the hoses -12 tothe teat cups, causing the milk to flow. The milk enters thev valve casings through the hoses t2 andfows inte the float chambers, raising the floats 23 therein until they bear against the valve arms 28'a`nd further elevate the latter topermit the latchemem-L Thereafter, when the float chamber 4 bers 32 to fall clear of the stop shoulders 33. However, the valves 21 remain open at this time because they are held up by the floats 23.

As the milk is exhausted from each teat, the ow of milk from that teat through the hose I2 into the valve casing I8 ceases, whereupon the milk level in the float chamber drops because of the constant drainage through the bleeder hole 25. The float 23 follows: the liquid down, and closes. the valve 21 stopping the application of suction through the outlet passage 26. However,

y hole.

This breaks all connection between the valve casing I8 and the tank lll, so that there is nolonger any suction applied to the valve casing,

and the existing vacuum is soon eliminated by entry of atmospheric air through the small pinhole bleeder hole. Thereupon, the milking action is terminated.

' Althoughfor` the purposev of explaining the invention, a .particular embodiment thereof has been.

shown and described,` obvious modications will occur tof a personskilled in the art, and I do not desireto be limited tothe exact details illustrated.

llclaim:

l-. An 'automatic valve mechanism for a milkingmachine having a tank, said mechanism comprising: a valve casing dening a float chamber and having a teat connection, an outlet passage tosaid' tank, and ableeder passage to said tank, said outlet passage having a valve seat in communication with its inner end; a valveand a pivoted valve arm in said casing supporting the valve for'movement toward and away from said seat, a portion of said arm extending across said float chamber; and a float in said float chamber under said Valve arm for lifting said arm to open said valve in response to milk in said chamber.

2. An automatic' valve mechanism for a milking machine in accordance with claim 1 in which said bleeder passage is in Vthe'bottom of said float chamber, and said float is a hollow sphere of rubber-like material adapted to seal off said bleeder passage' when .said oat is resting inthe-bottom of said float chamber.

3;. An automatic valve mechanism for a milking machine in accordance with claim 2 in which the `.bottom of the float chamber is shaped to dene a circular valve seat surrounding. said bleeder passage and of lesser diameter than said iloat.

4. An automatic valve mechanismfcr a milking machine in accordance withr claim 1 including a latch member pivotally secured to said valve arm whereby it. depends verticallyV therefrom when un-V restrained;. and a. stop for engaging the lower end of,.said latch memberand holding said valve arm in open Valve position, said stop. being laterally displaced from the pivot point of said latch member whereby theflatchy swings clear` of said stop in .responsetto elevation of. said valve arm by p flangesbffsaid valve.-v arm, said crossbar constipost having a shoulder thereon constituting said stop.

6. A n automatic valve mechanism for a milking machine according to claim 1 in which said valve casing comprises a body member defining the bottom and side Walls and having a, flange projecting inwardly from the side walls adjacent the upper edges thereof, a transparent cover plate Within said side Walls and above said ange; and a gasket on the edge of said cover frictionally engaging said side Walls and sealing with said flange.

'1. An automatic valve mechanism for a milking machine in accordance With claim 6 in which said cover plate contains a pinhole for equalizing the pressure in said valve casing.

8. An automatic valve mechanism for a milking machine in accordance with claim 1 in which 6 said valve casing comprises a body member defining the bottom and side walls and having a ange projecting inwardly from the side walls adjacent the upper edges thereof; and a cover plate seating against said flange; said float cornprising a hollow sphere of rubber-like material of greater diameter than the Width of the passage defined by said flange.

MARION K. EADES.

REFERENCES CITED UNITED STATES PATENTS Name Date Poarmann Aug. 27, 1918 Number 

